--- /dev/null
+/* Locking in multithreaded situations.
+ Copyright (C) 2005 Free Software Foundation, Inc.
+
+ This program is free software; you can redistribute it and/or modify it
+ under the terms of the GNU Library General Public License as published
+ by the Free Software Foundation; either version 2, or (at your option)
+ any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Library General Public License for more details.
+
+ You should have received a copy of the GNU Library General Public
+ License along with this program; if not, write to the Free Software
+ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
+ USA. */
+
+/* Written by Bruno Haible <bruno@clisp.org>, 2005.
+ Based on GCC's gthr-posix.h, gthr-posix95.h, gthr-solaris.h,
+ gthr-win32.h. */
+
+/* This file contains locking primitives for use with a given thread library.
+ It does not contain primitives for creating threads or for other
+ synchronization primitives.
+
+ Normal (non-recursive) locks:
+ Type: gl_lock_t
+ Declaration: gl_lock_define(extern, name)
+ Initializer: gl_lock_define_initialized(, name)
+ Initialization: gl_lock_init (name);
+ Taking the lock: gl_lock_lock (name);
+ Releasing the lock: gl_lock_unlock (name);
+ De-initialization: gl_lock_destroy (name);
+
+ Read-Write (non-recursive) locks:
+ Type: gl_rwlock_t
+ Declaration: gl_rwlock_define(extern, name)
+ Initializer: gl_rwlock_define_initialized(, name)
+ Initialization: gl_rwlock_init (name);
+ Taking the lock: gl_rwlock_rdlock (name);
+ gl_rwlock_wrlock (name);
+ Releasing the lock: gl_rwlock_unlock (name);
+ De-initialization: gl_rwlock_destroy (name);
+
+ Recursive locks:
+ Type: gl_recursive_lock_t
+ Declaration: gl_recursive_lock_define(extern, name)
+ Initializer: gl_recursive_lock_define_initialized(, name)
+ Initialization: gl_recursive_lock_init (name);
+ Taking the lock: gl_recursive_lock_lock (name);
+ Releasing the lock: gl_recursive_lock_unlock (name);
+ De-initialization: gl_recursive_lock_destroy (name);
+
+ Once-only execution:
+ Type: gl_once_t
+ Initializer: gl_once_define(extern, name)
+ Execution: gl_once (name, initfunction);
+*/
+
+
+#ifndef _LOCK_H
+#define _LOCK_H
+
+/* ========================================================================= */
+
+#if USE_POSIX_THREADS
+
+/* Use the POSIX threads library. */
+
+# include <pthread.h>
+# include <stdlib.h>
+
+# if PTHREAD_IN_USE_DETECTION_HARD
+
+/* The pthread_in_use() detection needs to be done at runtime. */
+# define pthread_in_use() \
+ glthread_in_use ()
+extern int glthread_in_use (void);
+
+# endif
+
+# if USE_POSIX_THREADS_WEAK
+
+/* Use weak references to the POSIX threads library. */
+
+/* Weak references avoid dragging in external libraries if the other parts
+ of the program don't use them. Here we use them, because we don't want
+ every program that uses libintl to depend on libpthread. This assumes
+ that libpthread would not be loaded after libintl; i.e. if libintl is
+ loaded first, by an executable that does not depend on libpthread, and
+ then a module is dynamically loaded that depends on libpthread, libintl
+ will not be multithread-safe. */
+
+/* The way to test at runtime whether libpthread is present is to test
+ whether a function pointer's value, such as &pthread_mutex_init, is
+ non-NULL. However, some versions of GCC have a bug through which, in
+ PIC mode, &foo != NULL always evaluates to true if there is a direct
+ call to foo(...) in the same function. To avoid this, we test the
+ address of a function in libpthread that we don't use. */
+
+# pragma weak pthread_mutex_init
+# pragma weak pthread_mutex_lock
+# pragma weak pthread_mutex_unlock
+# pragma weak pthread_mutex_destroy
+# pragma weak pthread_rwlock_init
+# pragma weak pthread_rwlock_rdlock
+# pragma weak pthread_rwlock_wrlock
+# pragma weak pthread_rwlock_unlock
+# pragma weak pthread_rwlock_destroy
+# pragma weak pthread_once
+# pragma weak pthread_cond_init
+# pragma weak pthread_cond_wait
+# pragma weak pthread_cond_signal
+# pragma weak pthread_cond_broadcast
+# pragma weak pthread_cond_destroy
+# pragma weak pthread_mutexattr_init
+# pragma weak pthread_mutexattr_settype
+# pragma weak pthread_mutexattr_destroy
+# ifndef pthread_self
+# pragma weak pthread_self
+# endif
+
+# if !PTHREAD_IN_USE_DETECTION_HARD
+# pragma weak pthread_cancel
+# define pthread_in_use() (pthread_cancel != NULL)
+# endif
+
+# else
+
+# if !PTHREAD_IN_USE_DETECTION_HARD
+# define pthread_in_use() 1
+# endif
+
+# endif
+
+/* -------------------------- gl_lock_t datatype -------------------------- */
+
+typedef pthread_mutex_t gl_lock_t;
+# define gl_lock_define(STORAGECLASS, NAME) \
+ STORAGECLASS pthread_mutex_t NAME;
+# define gl_lock_define_initialized(STORAGECLASS, NAME) \
+ STORAGECLASS pthread_mutex_t NAME = gl_lock_initializer;
+# define gl_lock_initializer \
+ PTHREAD_MUTEX_INITIALIZER
+# define gl_lock_init(NAME) \
+ if (pthread_in_use () && pthread_mutex_init (&NAME, NULL) != 0) abort ()
+# define gl_lock_lock(NAME) \
+ if (pthread_in_use () && pthread_mutex_lock (&NAME) != 0) abort ()
+# define gl_lock_unlock(NAME) \
+ if (pthread_in_use () && pthread_mutex_unlock (&NAME) != 0) abort ()
+# define gl_lock_destroy(NAME) \
+ if (pthread_in_use () && pthread_mutex_destroy (&NAME) != 0) abort ()
+
+/* ------------------------- gl_rwlock_t datatype ------------------------- */
+
+# if HAVE_PTHREAD_RWLOCK
+
+# ifdef PTHREAD_RWLOCK_INITIALIZER
+
+typedef pthread_rwlock_t gl_rwlock_t;
+# define gl_rwlock_define(STORAGECLASS, NAME) \
+ STORAGECLASS pthread_rwlock_t NAME;
+# define gl_rwlock_define_initialized(STORAGECLASS, NAME) \
+ STORAGECLASS pthread_rwlock_t NAME = gl_rwlock_initializer;
+# define gl_rwlock_initializer \
+ PTHREAD_RWLOCK_INITIALIZER
+# define gl_rwlock_init(NAME) \
+ if (pthread_in_use () && pthread_rwlock_init (&NAME, NULL) != 0) abort ()
+# define gl_rwlock_rdlock(NAME) \
+ if (pthread_in_use () && pthread_rwlock_rdlock (&NAME) != 0) abort ()
+# define gl_rwlock_wrlock(NAME) \
+ if (pthread_in_use () && pthread_rwlock_wrlock (&NAME) != 0) abort ()
+# define gl_rwlock_unlock(NAME) \
+ if (pthread_in_use () && pthread_rwlock_unlock (&NAME) != 0) abort ()
+# define gl_rwlock_destroy(NAME) \
+ if (pthread_in_use () && pthread_rwlock_destroy (&NAME) != 0) abort ()
+
+# else
+
+typedef struct
+ {
+ int initialized;
+ pthread_mutex_t guard; /* protects the initialization */
+ pthread_rwlock_t rwlock; /* read-write lock */
+ }
+ gl_rwlock_t;
+# define gl_rwlock_define(STORAGECLASS, NAME) \
+ STORAGECLASS gl_rwlock_t NAME;
+# define gl_rwlock_define_initialized(STORAGECLASS, NAME) \
+ STORAGECLASS gl_rwlock_t NAME = gl_rwlock_initializer;
+# define gl_rwlock_initializer \
+ { 0, PTHREAD_MUTEX_INITIALIZER }
+# define gl_rwlock_init(NAME) \
+ if (pthread_in_use ()) glthread_rwlock_init (&NAME)
+# define gl_rwlock_rdlock(NAME) \
+ if (pthread_in_use ()) glthread_rwlock_rdlock (&NAME)
+# define gl_rwlock_wrlock(NAME) \
+ if (pthread_in_use ()) glthread_rwlock_wrlock (&NAME)
+# define gl_rwlock_unlock(NAME) \
+ if (pthread_in_use ()) glthread_rwlock_unlock (&NAME)
+# define gl_rwlock_destroy(NAME) \
+ if (pthread_in_use ()) glthread_rwlock_destroy (&NAME)
+extern void glthread_rwlock_init (gl_rwlock_t *lock);
+extern void glthread_rwlock_rdlock (gl_rwlock_t *lock);
+extern void glthread_rwlock_wrlock (gl_rwlock_t *lock);
+extern void glthread_rwlock_unlock (gl_rwlock_t *lock);
+extern void glthread_rwlock_destroy (gl_rwlock_t *lock);
+
+# endif
+
+# else
+
+typedef struct
+ {
+ pthread_mutex_t lock; /* protects the remaining fields */
+ pthread_cond_t waiting_readers; /* waiting readers */
+ pthread_cond_t waiting_writers; /* waiting writers */
+ unsigned int waiting_writers_count; /* number of waiting writers */
+ int runcount; /* number of readers running, or -1 when a writer runs */
+ }
+ gl_rwlock_t;
+# define gl_rwlock_define(STORAGECLASS, NAME) \
+ STORAGECLASS gl_rwlock_t NAME;
+# define gl_rwlock_define_initialized(STORAGECLASS, NAME) \
+ STORAGECLASS gl_rwlock_t NAME = gl_rwlock_initializer;
+# define gl_rwlock_initializer \
+ { PTHREAD_MUTEX_INITIALIZER, PTHREAD_COND_INITIALIZER, PTHREAD_COND_INITIALIZER, 0, 0 }
+# define gl_rwlock_init(NAME) \
+ if (pthread_in_use ()) glthread_rwlock_init (&NAME)
+# define gl_rwlock_rdlock(NAME) \
+ if (pthread_in_use ()) glthread_rwlock_rdlock (&NAME)
+# define gl_rwlock_wrlock(NAME) \
+ if (pthread_in_use ()) glthread_rwlock_wrlock (&NAME)
+# define gl_rwlock_unlock(NAME) \
+ if (pthread_in_use ()) glthread_rwlock_unlock (&NAME)
+# define gl_rwlock_destroy(NAME) \
+ if (pthread_in_use ()) glthread_rwlock_destroy (&NAME)
+extern void glthread_rwlock_init (gl_rwlock_t *lock);
+extern void glthread_rwlock_rdlock (gl_rwlock_t *lock);
+extern void glthread_rwlock_wrlock (gl_rwlock_t *lock);
+extern void glthread_rwlock_unlock (gl_rwlock_t *lock);
+extern void glthread_rwlock_destroy (gl_rwlock_t *lock);
+
+# endif
+
+/* --------------------- gl_recursive_lock_t datatype --------------------- */
+
+# if HAVE_PTHREAD_MUTEX_RECURSIVE
+
+# if defined PTHREAD_RECURSIVE_MUTEX_INITIALIZER || defined PTHREAD_RECURSIVE_MUTEX_INITIALIZER_NP
+
+typedef pthread_mutex_t gl_recursive_lock_t;
+# define gl_recursive_lock_define(STORAGECLASS, NAME) \
+ STORAGECLASS pthread_mutex_t NAME;
+# define gl_recursive_lock_define_initialized(STORAGECLASS, NAME) \
+ STORAGECLASS pthread_mutex_t NAME = gl_recursive_lock_initializer;
+# ifdef PTHREAD_RECURSIVE_MUTEX_INITIALIZER
+# define gl_recursive_lock_initializer \
+ PTHREAD_RECURSIVE_MUTEX_INITIALIZER
+# else
+# define gl_recursive_lock_initializer \
+ PTHREAD_RECURSIVE_MUTEX_INITIALIZER_NP
+# endif
+# define gl_recursive_lock_init(NAME) \
+ if (pthread_in_use () && pthread_mutex_init (&NAME, NULL) != 0) abort ()
+# define gl_recursive_lock_lock(NAME) \
+ if (pthread_in_use () && pthread_mutex_lock (&NAME) != 0) abort ()
+# define gl_recursive_lock_unlock(NAME) \
+ if (pthread_in_use () && pthread_mutex_unlock (&NAME) != 0) abort ()
+# define gl_recursive_lock_destroy(NAME) \
+ if (pthread_in_use () && pthread_mutex_destroy (&NAME) != 0) abort ()
+
+# else
+
+typedef struct
+ {
+ pthread_mutex_t recmutex; /* recursive mutex */
+ pthread_mutex_t guard; /* protects the initialization */
+ int initialized;
+ }
+ gl_recursive_lock_t;
+# define gl_recursive_lock_define(STORAGECLASS, NAME) \
+ STORAGECLASS gl_recursive_lock_t NAME;
+# define gl_recursive_lock_define_initialized(STORAGECLASS, NAME) \
+ STORAGECLASS gl_recursive_lock_t NAME = gl_recursive_lock_initializer;
+# define gl_recursive_lock_initializer \
+ { PTHREAD_MUTEX_INITIALIZER, PTHREAD_MUTEX_INITIALIZER, 0 }
+# define gl_recursive_lock_init(NAME) \
+ if (pthread_in_use ()) glthread_recursive_lock_init (&NAME)
+# define gl_recursive_lock_lock(NAME) \
+ if (pthread_in_use ()) glthread_recursive_lock_lock (&NAME)
+# define gl_recursive_lock_unlock(NAME) \
+ if (pthread_in_use ()) glthread_recursive_lock_unlock (&NAME)
+# define gl_recursive_lock_destroy(NAME) \
+ if (pthread_in_use ()) glthread_recursive_lock_destroy (&NAME)
+extern void glthread_recursive_lock_init (gl_recursive_lock_t *lock);
+extern void glthread_recursive_lock_lock (gl_recursive_lock_t *lock);
+extern void glthread_recursive_lock_unlock (gl_recursive_lock_t *lock);
+extern void glthread_recursive_lock_destroy (gl_recursive_lock_t *lock);
+
+# endif
+
+# else
+
+/* Old versions of POSIX threads on Solaris did not have recursive locks.
+ We have to implement them ourselves. */
+
+typedef struct
+ {
+ pthread_mutex_t mutex;
+ pthread_t owner;
+ unsigned long depth;
+ }
+ gl_recursive_lock_t;
+# define gl_recursive_lock_define(STORAGECLASS, NAME) \
+ STORAGECLASS gl_recursive_lock_t NAME;
+# define gl_recursive_lock_define_initialized(STORAGECLASS, NAME) \
+ STORAGECLASS gl_recursive_lock_t NAME = gl_recursive_lock_initializer;
+# define gl_recursive_lock_initializer \
+ { PTHREAD_MUTEX_INITIALIZER, (pthread_t) 0, 0 }
+# define gl_recursive_lock_init(NAME) \
+ if (pthread_in_use ()) glthread_recursive_lock_init (&NAME)
+# define gl_recursive_lock_lock(NAME) \
+ if (pthread_in_use ()) glthread_recursive_lock_lock (&NAME)
+# define gl_recursive_lock_unlock(NAME) \
+ if (pthread_in_use ()) glthread_recursive_lock_unlock (&NAME)
+# define gl_recursive_lock_destroy(NAME) \
+ if (pthread_in_use ()) glthread_recursive_lock_destroy (&NAME)
+extern void glthread_recursive_lock_init (gl_recursive_lock_t *lock);
+extern void glthread_recursive_lock_lock (gl_recursive_lock_t *lock);
+extern void glthread_recursive_lock_unlock (gl_recursive_lock_t *lock);
+extern void glthread_recursive_lock_destroy (gl_recursive_lock_t *lock);
+
+# endif
+
+/* -------------------------- gl_once_t datatype -------------------------- */
+
+typedef pthread_once_t gl_once_t;
+# define gl_once_define(STORAGECLASS, NAME) \
+ STORAGECLASS pthread_once_t NAME = PTHREAD_ONCE_INIT;
+# define gl_once(NAME, INITFUNCTION) \
+ do \
+ { \
+ if (pthread_in_use ()) \
+ { \
+ if (pthread_once (&NAME, INITFUNCTION) != 0) \
+ abort (); \
+ } \
+ else \
+ { \
+ if (glthread_once_singlethreaded (&NAME)) \
+ INITFUNCTION (); \
+ } \
+ } \
+ while (0)
+extern int glthread_once_singlethreaded (pthread_once_t *once_control);
+
+#endif
+
+/* ========================================================================= */
+
+#if USE_PTH_THREADS
+
+/* Use the GNU Pth threads library. */
+
+# include <pth.h>
+# include <stdlib.h>
+
+# if USE_PTH_THREADS_WEAK
+
+/* Use weak references to the GNU Pth threads library. */
+
+# pragma weak pth_mutex_init
+# pragma weak pth_mutex_acquire
+# pragma weak pth_mutex_release
+# pragma weak pth_rwlock_init
+# pragma weak pth_rwlock_acquire
+# pragma weak pth_rwlock_release
+# pragma weak pth_once
+
+# pragma weak pth_cancel
+# define pth_in_use() (pth_cancel != NULL)
+
+# else
+
+# define pth_in_use() 1
+
+# endif
+
+/* -------------------------- gl_lock_t datatype -------------------------- */
+
+typedef pth_mutex_t gl_lock_t;
+# define gl_lock_define(STORAGECLASS, NAME) \
+ STORAGECLASS pth_mutex_t NAME;
+# define gl_lock_define_initialized(STORAGECLASS, NAME) \
+ STORAGECLASS pth_mutex_t NAME = gl_lock_initializer;
+# define gl_lock_initializer \
+ PTH_MUTEX_INIT
+# define gl_lock_init(NAME) \
+ if (pth_in_use() && !pth_mutex_init (&NAME)) abort ()
+# define gl_lock_lock(NAME) \
+ if (pth_in_use() && !pth_mutex_acquire (&NAME, 0, NULL)) abort ()
+# define gl_lock_unlock(NAME) \
+ if (pth_in_use() && !pth_mutex_release (&NAME)) abort ()
+# define gl_lock_destroy(NAME) \
+ (void)(&NAME)
+
+/* ------------------------- gl_rwlock_t datatype ------------------------- */
+
+typedef pth_rwlock_t gl_rwlock_t;
+# define gl_rwlock_define(STORAGECLASS, NAME) \
+ STORAGECLASS pth_rwlock_t NAME;
+# define gl_rwlock_define_initialized(STORAGECLASS, NAME) \
+ STORAGECLASS pth_rwlock_t NAME = gl_rwlock_initializer;
+# define gl_rwlock_initializer \
+ PTH_RWLOCK_INIT
+# define gl_rwlock_init(NAME) \
+ if (pth_in_use() && !pth_rwlock_init (&NAME)) abort ()
+# define gl_rwlock_rdlock(NAME) \
+ if (pth_in_use() && !pth_rwlock_acquire (&NAME, PTH_RWLOCK_RD, 0, NULL)) abort ()
+# define gl_rwlock_wrlock(NAME) \
+ if (pth_in_use() && !pth_rwlock_acquire (&NAME, PTH_RWLOCK_RW, 0, NULL)) abort ()
+# define gl_rwlock_unlock(NAME) \
+ if (pth_in_use() && !pth_rwlock_release (&NAME)) abort ()
+# define gl_rwlock_destroy(NAME) \
+ (void)(&NAME)
+
+/* --------------------- gl_recursive_lock_t datatype --------------------- */
+
+/* In Pth, mutexes are recursive by default. */
+typedef pth_mutex_t gl_recursive_lock_t;
+# define gl_recursive_lock_define(STORAGECLASS, NAME) \
+ STORAGECLASS pth_mutex_t NAME;
+# define gl_recursive_lock_define_initialized(STORAGECLASS, NAME) \
+ STORAGECLASS pth_mutex_t NAME = gl_recursive_lock_initializer;
+# define gl_recursive_lock_initializer \
+ PTH_MUTEX_INIT
+# define gl_recursive_lock_init(NAME) \
+ if (pth_in_use() && !pth_mutex_init (&NAME)) abort ()
+# define gl_recursive_lock_lock(NAME) \
+ if (pth_in_use() && !pth_mutex_acquire (&NAME, 0, NULL)) abort ()
+# define gl_recursive_lock_unlock(NAME) \
+ if (pth_in_use() && !pth_mutex_release (&NAME)) abort ()
+# define gl_recursive_lock_destroy(NAME) \
+ (void)(&NAME)
+
+/* -------------------------- gl_once_t datatype -------------------------- */
+
+typedef pth_once_t gl_once_t;
+# define gl_once_define(STORAGECLASS, NAME) \
+ STORAGECLASS pth_once_t NAME = PTH_ONCE_INIT;
+# define gl_once(NAME, INITFUNCTION) \
+ do \
+ { \
+ if (pth_in_use ()) \
+ { \
+ void (*gl_once_temp) (void) = INITFUNCTION; \
+ if (!pth_once (&NAME, glthread_once_call, &gl_once_temp)) \
+ abort (); \
+ } \
+ else \
+ { \
+ if (glthread_once_singlethreaded (&NAME)) \
+ INITFUNCTION (); \
+ } \
+ } \
+ while (0)
+extern void glthread_once_call (void *arg);
+extern int glthread_once_singlethreaded (pth_once_t *once_control);
+
+#endif
+
+/* ========================================================================= */
+
+#if USE_SOLARIS_THREADS
+
+/* Use the old Solaris threads library. */
+
+# include <thread.h>
+# include <synch.h>
+# include <stdlib.h>
+
+# if USE_SOLARIS_THREADS_WEAK
+
+/* Use weak references to the old Solaris threads library. */
+
+# pragma weak mutex_init
+# pragma weak mutex_lock
+# pragma weak mutex_unlock
+# pragma weak mutex_destroy
+# pragma weak rwlock_init
+# pragma weak rw_rdlock
+# pragma weak rw_wrlock
+# pragma weak rw_unlock
+# pragma weak rwlock_destroy
+# pragma weak thr_self
+
+# pragma weak thr_suspend
+# define thread_in_use() (thr_suspend != NULL)
+
+# else
+
+# define thread_in_use() 1
+
+# endif
+
+/* -------------------------- gl_lock_t datatype -------------------------- */
+
+typedef mutex_t gl_lock_t;
+# define gl_lock_define(STORAGECLASS, NAME) \
+ STORAGECLASS mutex_t NAME;
+# define gl_lock_define_initialized(STORAGECLASS, NAME) \
+ STORAGECLASS mutex_t NAME = gl_lock_initializer;
+# define gl_lock_initializer \
+ DEFAULTMUTEX
+# define gl_lock_init(NAME) \
+ if (thread_in_use () && mutex_init (&NAME, USYNC_THREAD, NULL) != 0) abort ()
+# define gl_lock_lock(NAME) \
+ if (thread_in_use () && mutex_lock (&NAME) != 0) abort ()
+# define gl_lock_unlock(NAME) \
+ if (thread_in_use () && mutex_unlock (&NAME) != 0) abort ()
+# define gl_lock_destroy(NAME) \
+ if (thread_in_use () && mutex_destroy (&NAME) != 0) abort ()
+
+/* ------------------------- gl_rwlock_t datatype ------------------------- */
+
+typedef rwlock_t gl_rwlock_t;
+# define gl_rwlock_define(STORAGECLASS, NAME) \
+ STORAGECLASS rwlock_t NAME;
+# define gl_rwlock_define_initialized(STORAGECLASS, NAME) \
+ STORAGECLASS rwlock_t NAME = gl_rwlock_initializer;
+# define gl_rwlock_initializer \
+ DEFAULTRWLOCK
+# define gl_rwlock_init(NAME) \
+ if (thread_in_use () && rwlock_init (&NAME, USYNC_THREAD, NULL) != 0) abort ()
+# define gl_rwlock_rdlock(NAME) \
+ if (thread_in_use () && rw_rdlock (&NAME) != 0) abort ()
+# define gl_rwlock_wrlock(NAME) \
+ if (thread_in_use () && rw_wrlock (&NAME) != 0) abort ()
+# define gl_rwlock_unlock(NAME) \
+ if (thread_in_use () && rw_unlock (&NAME) != 0) abort ()
+# define gl_rwlock_destroy(NAME) \
+ if (thread_in_use () && rwlock_destroy (&NAME) != 0) abort ()
+
+/* --------------------- gl_recursive_lock_t datatype --------------------- */
+
+/* Old Solaris threads did not have recursive locks.
+ We have to implement them ourselves. */
+
+typedef struct
+ {
+ mutex_t mutex;
+ thread_t owner;
+ unsigned long depth;
+ }
+ gl_recursive_lock_t;
+# define gl_recursive_lock_define(STORAGECLASS, NAME) \
+ STORAGECLASS gl_recursive_lock_t NAME;
+# define gl_recursive_lock_define_initialized(STORAGECLASS, NAME) \
+ STORAGECLASS gl_recursive_lock_t NAME = gl_recursive_lock_initializer;
+# define gl_recursive_lock_initializer \
+ { DEFAULTMUTEX, (thread_t) 0, 0 }
+# define gl_recursive_lock_init(NAME) \
+ if (thread_in_use ()) glthread_recursive_lock_init (&NAME)
+# define gl_recursive_lock_lock(NAME) \
+ if (thread_in_use ()) glthread_recursive_lock_lock (&NAME)
+# define gl_recursive_lock_unlock(NAME) \
+ if (thread_in_use ()) glthread_recursive_lock_unlock (&NAME)
+# define gl_recursive_lock_destroy(NAME) \
+ if (thread_in_use ()) glthread_recursive_lock_destroy (&NAME)
+extern void glthread_recursive_lock_init (gl_recursive_lock_t *lock);
+extern void glthread_recursive_lock_lock (gl_recursive_lock_t *lock);
+extern void glthread_recursive_lock_unlock (gl_recursive_lock_t *lock);
+extern void glthread_recursive_lock_destroy (gl_recursive_lock_t *lock);
+
+/* -------------------------- gl_once_t datatype -------------------------- */
+
+typedef struct
+ {
+ volatile int inited;
+ mutex_t mutex;
+ }
+ gl_once_t;
+# define gl_once_define(STORAGECLASS, NAME) \
+ STORAGECLASS gl_once_t NAME = { 0, DEFAULTMUTEX };
+# define gl_once(NAME, INITFUNCTION) \
+ do \
+ { \
+ if (thread_in_use ()) \
+ { \
+ glthread_once (&NAME, INITFUNCTION); \
+ } \
+ else \
+ { \
+ if (glthread_once_singlethreaded (&NAME)) \
+ INITFUNCTION (); \
+ } \
+ } \
+ while (0)
+extern void glthread_once (gl_once_t *once_control, void (*initfunction) (void));
+extern int glthread_once_singlethreaded (gl_once_t *once_control);
+
+#endif
+
+/* ========================================================================= */
+
+#if USE_WIN32_THREADS
+
+# include <windows.h>
+
+/* We can use CRITICAL_SECTION directly, rather than the Win32 Event, Mutex,
+ Semaphore types, because
+ - we need only to synchronize inside a single process (address space),
+ not inter-process locking,
+ - we don't need to support trylock operations. (TryEnterCriticalSection
+ does not work on Windows 95/98/ME. Packages that need trylock usually
+ define their own mutex type.) */
+
+/* There is no way to statically initialize a CRITICAL_SECTION. It needs
+ to be done lazily, once only. For this we need spinlocks. */
+
+typedef struct { volatile int done; volatile long started; } gl_spinlock_t;
+
+/* -------------------------- gl_lock_t datatype -------------------------- */
+
+typedef struct
+ {
+ gl_spinlock_t guard; /* protects the initialization */
+ CRITICAL_SECTION lock;
+ }
+ gl_lock_t;
+# define gl_lock_define(STORAGECLASS, NAME) \
+ STORAGECLASS gl_lock_t NAME;
+# define gl_lock_define_initialized(STORAGECLASS, NAME) \
+ STORAGECLASS gl_lock_t NAME = gl_lock_initializer;
+# define gl_lock_initializer \
+ { { 0, -1 } }
+# define gl_lock_init(NAME) \
+ glthread_lock_init (&NAME)
+# define gl_lock_lock(NAME) \
+ glthread_lock_lock (&NAME)
+# define gl_lock_unlock(NAME) \
+ glthread_lock_unlock (&NAME)
+# define gl_lock_destroy(NAME) \
+ glthread_lock_destroy (&NAME)
+extern void glthread_lock_init (gl_lock_t *lock);
+extern void glthread_lock_lock (gl_lock_t *lock);
+extern void glthread_lock_unlock (gl_lock_t *lock);
+extern void glthread_lock_destroy (gl_lock_t *lock);
+
+/* ------------------------- gl_rwlock_t datatype ------------------------- */
+
+/* It is impossible to implement read-write locks using plain locks, without
+ introducing an extra thread dedicated to managing read-write locks.
+ Therefore here we need to use the low-level Event type. */
+
+typedef struct
+ {
+ HANDLE *array; /* array of waiting threads, each represented by an event */
+ unsigned int count; /* number of waiting threads */
+ unsigned int alloc; /* length of allocated array */
+ unsigned int offset; /* index of first waiting thread in array */
+ }
+ gl_waitqueue_t;
+typedef struct
+ {
+ gl_spinlock_t guard; /* protects the initialization */
+ CRITICAL_SECTION lock; /* protects the remaining fields */
+ gl_waitqueue_t waiting_readers; /* waiting readers */
+ gl_waitqueue_t waiting_writers; /* waiting writers */
+ int runcount; /* number of readers running, or -1 when a writer runs */
+ }
+ gl_rwlock_t;
+# define gl_rwlock_define(STORAGECLASS, NAME) \
+ STORAGECLASS gl_rwlock_t NAME;
+# define gl_rwlock_define_initialized(STORAGECLASS, NAME) \
+ STORAGECLASS gl_rwlock_t NAME = gl_rwlock_initializer;
+# define gl_rwlock_initializer \
+ { { 0, -1 } }
+# define gl_rwlock_init(NAME) \
+ glthread_rwlock_init (&NAME)
+# define gl_rwlock_rdlock(NAME) \
+ glthread_rwlock_rdlock (&NAME)
+# define gl_rwlock_wrlock(NAME) \
+ glthread_rwlock_wrlock (&NAME)
+# define gl_rwlock_unlock(NAME) \
+ glthread_rwlock_unlock (&NAME)
+# define gl_rwlock_destroy(NAME) \
+ glthread_rwlock_destroy (&NAME)
+extern void glthread_rwlock_init (gl_rwlock_t *lock);
+extern void glthread_rwlock_rdlock (gl_rwlock_t *lock);
+extern void glthread_rwlock_wrlock (gl_rwlock_t *lock);
+extern void glthread_rwlock_unlock (gl_rwlock_t *lock);
+extern void glthread_rwlock_destroy (gl_rwlock_t *lock);
+
+/* --------------------- gl_recursive_lock_t datatype --------------------- */
+
+/* The Win32 documentation says that CRITICAL_SECTION already implements a
+ recursive lock. But we need not rely on it: It's easy to implement a
+ recursive lock without this assumption. */
+
+typedef struct
+ {
+ gl_spinlock_t guard; /* protects the initialization */
+ DWORD owner;
+ unsigned long depth;
+ CRITICAL_SECTION lock;
+ }
+ gl_recursive_lock_t;
+# define gl_recursive_lock_define(STORAGECLASS, NAME) \
+ STORAGECLASS gl_recursive_lock_t NAME;
+# define gl_recursive_lock_define_initialized(STORAGECLASS, NAME) \
+ STORAGECLASS gl_recursive_lock_t NAME = gl_recursive_lock_initializer;
+# define gl_recursive_lock_initializer \
+ { { 0, -1 }, 0, 0 }
+# define gl_recursive_lock_init(NAME) \
+ glthread_recursive_lock_init (&NAME)
+# define gl_recursive_lock_lock(NAME) \
+ glthread_recursive_lock_lock (&NAME)
+# define gl_recursive_lock_unlock(NAME) \
+ glthread_recursive_lock_unlock (&NAME)
+# define gl_recursive_lock_destroy(NAME) \
+ glthread_recursive_lock_destroy (&NAME)
+extern void glthread_recursive_lock_init (gl_recursive_lock_t *lock);
+extern void glthread_recursive_lock_lock (gl_recursive_lock_t *lock);
+extern void glthread_recursive_lock_unlock (gl_recursive_lock_t *lock);
+extern void glthread_recursive_lock_destroy (gl_recursive_lock_t *lock);
+
+/* -------------------------- gl_once_t datatype -------------------------- */
+
+typedef struct
+ {
+ volatile int inited;
+ volatile long started;
+ CRITICAL_SECTION lock;
+ }
+ gl_once_t;
+# define gl_once_define(STORAGECLASS, NAME) \
+ STORAGECLASS gl_once_t NAME = { -1, -1 };
+# define gl_once(NAME, INITFUNCTION) \
+ glthread_once (&NAME, INITFUNCTION)
+extern void glthread_once (gl_once_t *once_control, void (*initfunction) (void));
+
+#endif
+
+/* ========================================================================= */
+
+#if !(USE_POSIX_THREADS || USE_PTH_THREADS || USE_SOLARIS_THREADS || USE_WIN32_THREADS)
+
+/* Provide dummy implementation if threads are not supported. */
+
+/* -------------------------- gl_lock_t datatype -------------------------- */
+
+typedef int gl_lock_t;
+# define gl_lock_define(STORAGECLASS, NAME)
+# define gl_lock_define_initialized(STORAGECLASS, NAME)
+# define gl_lock_init(NAME)
+# define gl_lock_lock(NAME)
+# define gl_lock_unlock(NAME)
+
+/* ------------------------- gl_rwlock_t datatype ------------------------- */
+
+typedef int gl_rwlock_t;
+# define gl_rwlock_define(STORAGECLASS, NAME)
+# define gl_rwlock_define_initialized(STORAGECLASS, NAME)
+# define gl_rwlock_init(NAME)
+# define gl_rwlock_rdlock(NAME)
+# define gl_rwlock_wrlock(NAME)
+# define gl_rwlock_unlock(NAME)
+
+/* --------------------- gl_recursive_lock_t datatype --------------------- */
+
+typedef int gl_recursive_lock_t;
+# define gl_recursive_lock_define(STORAGECLASS, NAME)
+# define gl_recursive_lock_define_initialized(STORAGECLASS, NAME)
+# define gl_recursive_lock_init(NAME)
+# define gl_recursive_lock_lock(NAME)
+# define gl_recursive_lock_unlock(NAME)
+
+/* -------------------------- gl_once_t datatype -------------------------- */
+
+typedef int gl_once_t;
+# define gl_once_define(STORAGECLASS, NAME) \
+ STORAGECLASS gl_once_t NAME = 0;
+# define gl_once(NAME, INITFUNCTION) \
+ do \
+ { \
+ if (NAME == 0) \
+ { \
+ NAME = ~ 0; \
+ INITFUNCTION (); \
+ } \
+ } \
+ while (0)
+
+#endif
+
+/* ========================================================================= */
+
+#endif /* _LOCK_H */
projects / apps / madmutt.git / blobdiff